Refrigerating apparatus with hot gas defrost means



Oct. 25, 1960 B. M. BUCHANAN 2,

REFRIGERATING APPARATUS WITH HOT GAS DEFROST ME NS Filed Aug. 29, 1957 2 Sheets-Sheet 1 \NVENTOR LESLIE B. M. BUCHANAN ATTO NEY .Oct. 25, 1960 1.. B. M. BUCHANAN 2,957,316

REFRIGERATING APPARATUS WITH HOT GAS DEFROST MEANS Filed Aug. 29, 1957 2 Sheets-Sheet 2 1m 1 59 72 68 5 ea 59 n II E Valve Cloud INVENTOR LESLIE B.M. BUCHANAN Door 0 en Defrost ATTORNEY United States Patent 6 REFRIGERATING APPARATUSWIIH nor I ous nnrnosr MEANS 7 Leslie B. M. Buchanan, Galloway, Ohio, assignor to Westinghouse Electric Corporation,v Pittsburgh, Pa., a corporation of Pennsylvania Filed Aug. 29, I957, Ser. 110,681,028

4 Claims. (Cl. 61-153) This invention relates. to refrigerating apparatus and more particularly to an improved defrost control for a refrigerating system.

To insure efficient operation of a compressor-condenser-expander refrigerating systemit is desirable that the evaporator portion ofthe circuit be periodically elevated in temperature to above 32 F. to effect removal of ice and frost that collectsthereon. It has been previously proposed that defrosting of the evaporator be accomplished by modifying the operation of the refrigerating circuit to introduce hot gaseous refrigerant directly from the compressor into the evaporator, bypassing the condenser and the flow impeding device that is normally disposed in the circuit betweenthe condenser and the evaporator. The hot gas conveyed to the evaporator in this type. of defrosting. system is condensed in the evaporator, and the heat thereby given up raises thetemperature of the evaporator sufliciently to melt ice and frost therefrom; Systems embodying this defrosting arrangement are commonly called hot gas or bypass defrosting systems.

This invention provides an improved self-controlling valve for controlling refrigerant flow through the bypass conduit of the defrosting system. As will appear in greater detail below, actuation of the valve to initiate defrosting can be accomplished by manual or by automatic, periodically operated means. Termination of defrosting is accomplished by a unique arrangement that takes advantage of the increase in fluid pressure that normally occurs in the defrosting circuit upon the completion of defrosting of the evaporator; This increase in presssure results from the rapid. increase in temperature of the evaporator as all of the ice and frost has been removed therefrom. The preferred embodiment of the invention includes a pressure responsive bellows associated with the body of the valve controlling flow through the hot gas bypass conduit, which bellows is responsive to fluctuations in fluid pressure in the bypass conduit. A movable portion of the bellowsi coupled with the valve in such. a manner as to automatically close the valve upon the pressure in the bypass conduit rising to a predetermined value indicating that the temperature of the evaporator has been raised to a value above 32 F. and that defrosting of the evaporator is completed;

The invention provides a simple and inexpensive, yet reliable, control for defrostable refrigerating systems, which control is considerablyless complicated than prior control arrangements involving thermostats, or the like, for sensing the temperature of the evaporator, and consequently obtains the objective of improving defrostable refrigerating systems.

Other objects, advantages and features of this invention Will appear from the detailed description thereof which follows and which includes reference to the attached drawings wherein:

Fig. l is a diagrammatic illustration of a refrigerating system embodying this invention;

Patented Oct. 25, 1960 Fig. 2 is an enlarged cross-sectional viewof the improved defrost control;

Fig. 3- is a fragmentary sectional view through a refrigerator cabinet illustrating a modified form of the control mounted therein, and turther illustrating the cooperation between this. modified control and the door of the refrigerator;

Fig. 4 is an enlarged sectional view of the modified control;

Fig. 5 is a sectional view of a portion. of the control taken as indicated by the VV in Fig. 4; and

Figs. 6 and 7 are diagrammatic views of the modified control illustrating the relationship of the parts under various operating conditions.

Referring in detail to Fig. 1', the invention is particularly applicable to the conventional compressor-condenser-expander typerefiigerating circuit there illustrated; This circuit includes. a motor-compressor 11. for compressing refrigerant gas that is conveyed into a condenser 12. The compressed and condensed refrigerantis thereafter conveyed into an evaporator 13' by a flow impeding device in the form of a capillary, or small bore, tube 14. Thesecomponents of the refrigerating system are connected in series flow relationship by suitable conduits including a suction conduit 15 for returning vaporized refrigerant from the evaporator 13 to the motor compressor 11. Suitable controls, responsive to the temperature of evaporator 13, are normally provided for cyclingthe motor-compressor 11 to maintain a predetermined, below freezing temperature at the evaporator. Controls of this type are well known and well understood in the refrigeration art and, since a detailed discussion thereof would not enhance the description of the present invention, they have been omitted from. the drawings to clarify the illustration.

While operating on a refrigerating cycle, the evaporator 13 of the circuit collects frost and ice which must be periodically removed to insure efficient transfer of heat to the evaporator from the. surrounding media. Defrosting isaccomplished in the refrigerating circuit shown in Fig. 1 by conveying hot gaseous refrigerant directly from the motor-compressor 11 into the evaporator 13. The conveying. means for this purpose comprises a bypass conduit 16 connected. at one end to a hot gas conduit 17 carrying hot gaseous refrigerant from the motor compressor 11.. The discharge end of the bypass conduit 16 communicates directly with the evapo rator 13 in. such. a manner that the bypass conduit forms a parallel refrigerant flow path capable of bypassing both the condenser 13 and the capillary tube 14.

Initiation and termination of refrigerant flow through the bypass conduit 16 to, respectively, start and stop a defrosting operation is effected by a defrost control, indicated by the numeral 18, the details of construction of which are shown most clearly in. Fig. 2. The control 18 includes a shut-off valve 19 having a refrigerant flow passage 21 therein that communicates with and forms a part of the bypass conduit 16. Refrigerant flow through the passage 21 is selectively permitted or prevented by a valve member, or plunger. 22' cooperating with a valve seat 23 that is sealed in fiuid tight relationship between tube-like members that form the body 24 of the valve 19. Movement of the valve member 22 toward or away from the valve seat 23 is elfected by means of a valve stem 26 connected to the valve member and extending through a pressure responsive bellows 27 that is secured to one end of the valve body 24. The bellows 27; is preferably made of thin material having. highztensile strength, such as stainless steel or bronze, to permit the end wallthereof, indicated at 28 and to which the valve stem 26 is connected, to undergo movement. in response to fluctuations of fluid pressure within the valve passage 21 without stressing the bellows beyond its elastic limit. The bellows 27 is joined to the valve body 24 and to the valve stem 26 by brazing, welding or other suitable means for hermetically sealing the interior of the valve 19 to prevent the escape of refrigerant therefrom. The bellows 27 is protected from accidental damage by a casing 29 that also serves as a support and housing for an actuating lever 31 adapted to effect opening movement of the valve member 22. The arm 31 functions as a second class lever. It has a pivot pin 32 disposed near one end thereof, a bearing recess 33 disposed adjacent the pivot 32 for reception of an extension 34 of the valve stem 26, and a manually actuable plunger, or push button, 36 connected to its other end, in a manner to permit the valve 19 to be opened against the forces acting on the 'valve member 22 and the bellows 27 by a relatively small force applied to the plunger 36. The plunger 36 extends through an opening provided therefor in the control casing 29, and the casing is preferably located in, or on, the

refrigerator in a position to render the plunger readily accessible to the user of the refrigerator. An inward motion of the plunger 36 (upwardas viewed in Fig. 2) effects rotation of the actuating arm 31 about its pivot pin 32 and, acting through the valve stem 26, moves the valve 22 from its seat 23 to open the valve.

The control 18 further includes means for restraining the valve member 22 in its open position under the influence of a predetermined, but releasable, holding force. In the preferred embodiment, this result is accomplished by a detent mechanism comprising a spring catch 37 secured at one end to a bendable tab 38attached to the control casing 29. The catch has a hook or detent 39 therein that partially receives a roller 41 mounted on an :axle at the end of the actuating arm 31. The spring catch 7 37 is adapted to overlie the roller 41 and hold theactuating arm 31 in the position that the arm occupies when the valve member 22 is in its open position (the dotted line positions of these elements in Fig. 2). The arm 31 is releasable from the spring catch 37 upon the application of a predetermined force to the actuating arm sufi'icient to overcome the restraining force of the catch 37. Adjustment of the restraining force provided by the spring catch 37 can be effected in any suitable manner, for example, by bending the tab 38 by which the catch 37 is supported, to increase or decrease the force with which the detent 39 is held against the roller 41.

In accordance with this invention, the valve member 22 is automatically moved toward closed position against the valve seat 23 by an increase in pressure within the valve passage 21, which pressure increase manifests itself in a tendency toward extension of the bellows 27. During the defrosting period, and while frost and ice are being melted from the evaporator 13, the hot gas passing through the discharge conduit 16 is condensed in the evaporator 13 and liquid refrigerant is conveyed through the'suction conduit 15 and back to the motor compressor 11, where it is evaporated and again compressed. During defrosting, fluid pressure in the evaporator 13 and the bypass conduit 16 is of the order of 5 psi. As the defrosting proceeds and all of the ice and frost is removed from the evaporator 13, the temperature of the evaporator 13 rises rapidly, increasing the fluid pressure in the evaporator, and consequently increasing fluid pressure in the bypass conduit 16 and the valve passage 21. The rise in pressure in the valve passage 21 increases the force acting on the bellows'end wall 28. I This force is, in turn, transmitted to the actuating arm 31 by the valve stem extension 34 and tends to move the actuating arm 31 clockwise about its pivot pin 32. Eventually, the pressure rises to a point, say 40 p. s.i., where the force on the actuating arm 31 becomes greater than the restraining froce applied thereto by the spring catch 37 and the arm 31 is forced free of the catch, permitting the bellows 27 to move the valve member 23 to closed position, to prevent further flow of refrigerant through the bypass 16 and terminate the defrosting operation.

Modification Figs. 3 through 7 illustrate a modification of this invention in which the improved defrost control incorporates means for automatically and periodically actuating the defrost control valve to initiate defrosting in accordance with usage of the refrigerator. More specifically, the modified control, the casing for which is indicated generally by the numeral 51, includes amechanism for counting the number of times the refrigerator door is opened and for initiating defrosting after a predetermined number of door openings. The modified control further embodies the novel pressure sensing, defrost termination arrangement employed in the previously described embodiment of the invention.

Referring specifically to Fig. 3, which is a fragmentary illustration of a refrigerator cabinet, the control casing 51' is shown mounted within, and near the front edge of, an insulated wall 52 of the refrigerator cabinet, in a position in which a plunger 53, projecting from the front face of the casing 51, lies in the path of movement of a door 54 hingedly mounted on the cabinet. The mounting for the door 54 is not shown but it is to be understood that the mounting is such as to permit swinging movement of the door 54 toward and away from the cabinet wall 52 in a conventional manner. Each time the door 54 is moved to its closed position (Fig. 3) the plunger 53 is engaged by the door and moved inwardly of th control casing 51.

The details of the modified control are shown more clearly in Figs. 4 and 5 wherein it will be seen that the control includes a shut-off valve 19, similar to the valve 19 of Figs. 1 and 2 and adapted to control the flow of hot gaseous refrigerant through a bypass conduit 16 and to thereby control defrosting of a refrigerating system such as that shown in Fig.1 and described above. The modified control of Figs. 4 and 5 possesses other elements or components that are similar to elements and components employed in the previously described embodiment of the invention and, whenever possible, the same reference numerals are used to designate these components in both embodiments. For example, the modified control 51 also includes a pressure responsive bellows 27, hermetically sealed to the body of the valve 19 and capable of effecting opening movement of the components of the valve 19 when the pressure in the bypass conduit 16 increases sufiiciently to indicate completion of defrosting of the evaporator portion of the refrigerating circuit. The control further includes a pivotally mounted actuating arm 31 for opening the valve 19 to initiate defrosting. In Figs. 4 and 5 the actuating arm'31 is shown in the position that it occupies when the valve 19 is closed. Opening of the valve 19 is eifected by counterclockwise rotation of the actuating arm 31 about its pivot pin 32.

In place of the spring catch detent mechanism employed in the previously described embodiment. to hold the actuating arm 31 in its valve open position, a small permanent magnet 56, carried by the arm 31 and attractable to a magnetic armature strip 57 mounted in the control casing, is employed for this purpose. The restraining force exerted on the valve actuating arm 31 by the magnet 56 can be adjusted by means of a threaded bolt 58 that functions'as an adjustable stop for the arm 31 and which determines the minimum spacing between the magnet 56 and the armature strip 57.

In this modified control, periodic movement of the valve actuating arm 31 is automatically controlled by a ratchet type counter mechanism that is activated byopening and closing movements of the refrigerator door 54. The details of this mechanism are shown most clearly in Figs. 4 and 5. Movement of the actuating arm 31 is effected by a rocker arm 59 pivotally mounted inthe control casing 51, on a shaft 61. The rocker arm 59 carries a spring finger 62 on one end thereof in a position to engage the valve actuating arm 31. G'scillating movement of the rocker arm 59 is produced by a: compression spring 63 disposed between a yoke-like: end 64 of the rocker arm and the control casing 51. As can be seenfrom an examination of Fig. 4, the spring 63 biases the rocker arm 59 counterclockwise. Movementof the rocker arm 59 under the action of thecompression spring 63 is controlled by the door actuated plunger 53 that applies forces to the rocker arm in opposition to the: bias of spring 63 through another compression. spring 66 acting between a fixed abutment 67 on the plunger 53 and the yoke end 64 of the rocker arm 59. Each time the door 54 of the refrigerator cabinet is opened; spring 63 moves rocker arm 59 counterclockwise, in: a direction to open the defrost control valve 19. Closing movements of the door 54 cause the plunger 53 to move inwardly and effect clockwise rotation of the: rocker arm 59, moving the spring finger 62 away from the valve actuating arm 31. The spring 66 permits overtravel', i.e. relative movement, of the plunger 53 with respect to the rocker arm 59 which abuts a rotatable stop 681 that. limits clockwise rotation of the rocker arm 59.

The rotatable stop 68 is shaped like an inverted. drum member, and is mounted for rotation about the axis. of a shaft '69 carried by the control casing 51. The stop 68 is adapted to not only limit clockwise movement of the rocker arm 59 but also limit counterclockwise rotation of the rocker arm 59 to prevent engagement between the rocker arm finger 62 and the valve actuating arm 31 except when the stop 68 is in a particular, preselected position. The rocker arm 59 has a finger 71 projecting therefrom in a position to engage a drum-like surface 72 on the rotatable stop 68. In all but selected posit-ions of the stop 68, counterclockwise rotation, i.e. movement of the rocker arm 59 in a valve opening direction, is limited, or arrested, by finger 71 abutting the drum surface 72 of the stop 68. The stop surface 72, however, has an opening, or cut-out, 73 therein through which the rocker arm finger 71' can pass when the stop 68 is rotated to a position inwhich the opening 73 is in the path of movement of the finger 71 (see Fig. 7).

The stop 68 is adapted to be rotated counterclockwise, as viewed in Fig. 4, by means of ratchet teeth 74 formed in the periphery of the stop, and which teeth are engageable by a pair of cooperating spring pawls 76 and 77. The pawl 77 is carried by the yoke end 64 of the rocker arm 59 and is adapted to advance the rotatable stop 68 counterclockwise each time the refrigerator door 54 is opened. This action is illustrated in Figs. 4 and 6 of the drawings. Each time the door 54 is moved from its closed position (Fig. 4) to its open position (Fig. 6) plunger 53 is released and spring 63 rotates rocker arm 59 counterclockwise until the finger 71 on the rocker arm engages surface 72 of the stop 68. This movement of the rocker arm 59 is sufficient to advance the rotatable stop 68 through an arcuate distance at least equal to the length of one ratchet tooth 74. The spring pawl 76 acts as a stop to prevent reverse, or clockwise, rotation of the rotatable stop 68 as the door 54 is closed and the rocker arm 59 is rotated clockwise. causing the advancing' pawl 77 to ride over and engage the next ratchet tooth 74.

A succession of door opening and closing movements advances the rotatable stoo 68 to the position in which the opening 73 therein is in the path of movement of the rocker arm fin er 71. When this relationship of components is established. as illustrated in Fig. 7, the rocker arm finger 71 enters the openin 73 in the rotatable stop 68 and allows the rocker arm 59 to rotate counterclockwise through an additional angle of movement sufficient to cause the spring finger 62 to engage valve actuating arm 31 and move it to its valve opening position, causing opening of the valve 19 to initiate defrosting. The number of door openings and closings required to bring the elements of the control to this defrost initiating condition is. dependent. upon. the. number of ratchet; teeth 74. pit? videdion the. rotatable: stop 68. In the. case ofv a: domestic refrigerator, it has been determined that the. initiation of defrosting each time the refrigerator door has been opened some sixty times is: sufficient to prevent an undesirable accumulation. of frost on the refrigeratingcircuit evaporator.

It willibeznoted. from Fig. 7 that the additional movement' of the rocker arm 59 in approaching the position in which. it. effects opening of the valve 19, moves the advancing. pawl 77 an additional distance that causes the rotatable; stop 68. to move counterclockwise until. the edge of the opening 73 engages the rocker arm finger 71. This positioning of the rotatable stop 68 insures that, upon the. next door opening movement, the rotatable stop 68 will: be advanced by the. pawl 77 a distance sufli'cient to completely move the stop opening 73 out of. the path of movement of the rocker arm finger 71 and present. the stop surface 72 to the finger 71 and prevent initiation of defrosting until the stop 68 has again been rotated approximately one revolution.

The components of this modified control are so constructed as to prevent the defrost control valve 19 from reclosing'immediately after it has been opened. Referring to Fig. 2 wherein the details of the valve 19 are illustrated, it can be appreciated; that immediately after the valve member 22 is separated from its seat 23', as when defrosting is initiated, the valve member 22 is subjected to a rush. of high velocity refrigerant gas passing from the compression, or high pressure, side of the refrigerating system into the evaporative, or. low pressure, side of the system. This rush of gas around the valve member 22 tends to seat the valve member, i.e., close the valve 19, and while this closing movement is opposed by the restraining means, such as the magnet 56, in the embodiment illustrated in Fig. 7, in some instances the closing force may be sufiicient to overcome the action of the restraining means. In the modified control, however, since defrosting, i.e. opening of the valve 1 9, is always initiated by an opening movement of the refrigerator door, the force of compression spring 63 is applied to the valve actuating arm 31 through rocker arm 59 and spring finger 62 to assist in maintaining the valve 19 open during this initial, critical period. During normal use, the refrigerator door will be held open at least a-few seconds, which period of time is suificient to permit the initial excessive flow of refrigerant around the valve member 22 to subside so that, when the door is thereafter closed and the additional biasing force of spring 63- is removed from the valve actuating arm 31, the tendency for the valve 19 to close will have been considerably reduced and the magnet 56wi1-l thereafter be capable of maintaining the valve 19 open until the evaporator is completely defrosted.

The modified defrost control of Figs. 3 through 7 terminates defrosting of the refrigerating circuit in the same manner as the previously described embodiment of the control. The removal of frost and ice from the evaporator portion of the refrigerating circuit is accompanied by an increase in pressure in the bypass conduit 16 and the valve 19. The increased pressure, acting through the pressure responsive bellows. 27, applies. a force to the valve actuating arm 31 that is great enough to overcome the restraining force of the magnet 56 and the valve member 22 inside the valve 19 is rapidly moved to its closed position on its seat 23 by expansion of the bellows 27.

From the foregoing it will be apparent this. invention provides a novel and inexpensive control arrangement for automatically terminating a defrosting operation in a hot gas or bypass type defrostable refrigerating system; the simplicity of the control being due in part to the utilization of a bellows, or other device having a flexible Wall portion, that is employed as a pressure sensing means and also employed as a flexible wall portion of the refrigerant. flow control valve through which force and movement can be transmitted to the movable components of the valve. It should be apparent that a dia 'phragm type device could be substituted for the bellows 27 employed in the two embodiments of the invention described above, which diaphragm would function in the same manner as the bellows. It will further be apparent that the invention provides a novel mechanism and arrangement for initiating defrosting in a defrostable refrigerating system in response to the opening and closing of the refrigerator door. It should again be pointed out that this defrost initiating mechanism of the second embodiment of the invention is so constructed as to insure that the defrost control valve is held open during the initial phase of defrosting when gas rushing past themovable elements of the valve tend to effect predetermined closure of the valve.

While the invention has been shown in but two forms, it will be obvious to those skilled in the art that it is not so limited, but is susceptible of various other changes and modifications without departing from the spirit thereof.

What is claimed is:

1. In a refrigerating circuit comprising a compressor, a condenser, a flow impeding device, and an evaporator, said elements being connected in a series flow circuit, a bypass conduit connecting said compressor to said evaporator and adapted to convey =hot gaseous refrigerant to said evaporator to effect defrosting of said evaporator,

and means for control-ling the flow of refrigerant through said bypass conduit, said means comprising a valve body having a refrigerant fiow passage therethrou-gh, a valve member movable between open and closed positions for respectively'opening and closing said passage,

a bellows sealed to said valve body, said bellows having a'wall thereof movable in response to an increase in the pressure of refrigerant in said valve body, means for transmitting movement of said bellows wall to said valve member, the construction and arrangement being such that an increase in fluid pressure in said valve body said ratchet for rotating said ratchet and said stop a predetermined amount each time said lever is moved by said spring, the construction and arrangement being such that said spring acting through said lever assists said force applying means in retaining said valve in open position when said stop is in its said one position and the refrigerator door is open, and means for closing said valve and for releasing said force applying means.

3. In a refrigerator including a door movable between open and closed positions, a refrigerating system, means including a valve member for controlling operation of said system, said valve member being movable between open and closed positions, and means for actuating said valve member comprising; a pivoted lever movable in one direction to actuate said valve member to open position, a spring biasing said lever in said one direction, a plunger engageable by the door of the'refrigerator and adapted to move said lever in opposition to said spring as the door is moved to its closed position, a movable stop adapted to limit movement of said lever in said one direction, said stop having an opening therein eifective in one position of said stop to permit movement of said lever to actuate said valve member to open position, a ratchet .for moving said stop, a pawl calried by said lever and engageable with said ratchet for moving said ratchet and said stop a predetermined amount each time said lever is moved by said spring, and means for closing said valve.

4. The combination with a refrigerating circuit comprising a compressor, a condenser, a flow impeding device, and an evaporator, said elements being connected in V series flow relationship whereby said flow impeding device biases said bellows wall in a direction to move said I valve member toward its closed position, means disposed externally of the refrigerant circuit and including an actuating arm movable in one direction for moving said bellows wall in a direction to move said valve member to its open position, said arm being movable in the opposite direction by said bellows wall, and means for applying a predetermined restraining force to said actuating arm to prevent movement of said arm in said opposite direction when the fluid pressure in said valve body is below a predetermined value.

2. In a refrigerator including a door movable between open and closed positions, a refrigerating system, means including a valve member for controlling operation of said system, said valve member being movable between open and closed positions, and means for actuating said valve member comprising; releasable means for applying a predetermined restraining force to said valve member when the valve is in its open position to maintain said valve member in its said open position, a pivoted lever movable in one direction to actuate said valve member to open position, a spring biasing said lever in said one direction, a plunger engageable by the door of the refrigerator and adapted'to move said lever in opconveys liquid refrigerant to said evaporator for vaporization therein to cool said evaporator, of means for modifying the operation of said circuit to effect defrosting of said evaporator, said modifying means including a conduit bypassing the flow impeding device in said circuit for delivering uncondensed refrigerant to said evaporator, and control means for alternatively establishing or precluding refrigerant flow through said bypass conduit, said control means comprising a valve body having a refrigerant flow passage therethrough, a valve member movable between open and closed positions for respectively opening and closing said passage, said valve body having an opening therein, a flexible pressure responsive device secured in fluid-tight relation to said valve body and having the interior thereof in communication with the refrigerant circuit through said opening, said pressure responsive device having a portion thereof movable in response to an increase in the pressure of refrigerant circulating through said circuit, a movable member connecting said valve member to said movable portion of said pressure responsive device for transmitting movement of said portion of said pressure responsive device to 'said valve member, means disposed externally of the refrigerant circuit and including an actuating arm engageable with said movable member and movable in one direction to move said valve member to its open position, said arm being movable in the opposite direction to permit said pressure responsive. device to move said valve member to its closed position, and releasable means applying a predetermined force to said actuating arm to'restrain movement of said arm in said opposite direction when said valve member is in its open position and the fluid pressure in said device is below a predetermined value.

References Cited in the file of this patent V UNITED STATES PATENTS 2,524,568 Kritzer OCLB, 1950 2,548,324 Smith Apr. 10, 1951 2,737,025 Soreng Mar. 6, 1956 87 ,Hubacker May 1, 1956 

